RTCPeerConnection: datachannel event

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A datachannel event is sent to an RTCPeerConnection instance when an RTCDataChannel has been added to the connection, as a result of the remote peer calling RTCPeerConnection.createDataChannel().

Note: This event is not dispatched when the local end of the connection creates the channel.

This event is not cancelable and does not bubble.

Syntax

Use the event name in addEventListener():

addEventListener("datachannel", (event) => { })

Alternatively, assign to the event handler property of the interface:

ondatachannel = (event) => { }

Event type

An RTCDataChannelEvent. Inherits from Event.

This example sets up a function that handles datachannel events by gathering the information needed to communicate with the newly added RTCDataChannel and by adding event handlers for the events that occur on that channel.

pc.addEventListener("datachannel", (ev) => {
  receiveChannel = ev.channel;
  receiveChannel.onmessage = myHandleMessage;
  receiveChannel.onopen = myHandleOpen;
  receiveChannel.onclose = myHandleClose;
});

receiveChannel is set to the value of the event's channel property, which specifies the RTCDataChannel object representing the data channel linking the remote peer to the local one.

This same code can also instead use the RTCPeerConnection interface's ondatachannel event handler property, like this (but note that this replaces other event listeners added using ondatachannel, if any):

pc.ondatachannel = (ev) => {
  receiveChannel = ev.channel;
  receiveChannel.onmessage = myHandleMessage;
  receiveChannel.onopen = myHandleOpen;
  receiveChannel.onclose = myHandleClose;
};